Processes for effecting hydrocarbon production from reservoirs having a low permeability zone by cooling and heating

ABSTRACT

A process is provided for producing hydrocarbon material from a reservoir, including: cooling at least a portion of a low permeability zone within the reservoir with effect that water, disposed within the low permeability zone, freezes and expands, with effect that one or more flow paths are formed through the low permeability zone; mobilizing hydrocarbon material within the reservoir such that the mobilized hydrocarbon material is conducted through the low permeability zone via the one or more flow paths; and after the conduction of the mobilized hydrocarbon material through the low permeability zone via the one or more flow paths, producing the mobilized hydrocarbon material.

RELATED APPLICATION

This application is a continuation in part of PCT Internationalapplication no. PCT/CA2017/000067, filed 24 Mar. 2017, which claims allbenefit, including priority of, U.S. Application Nos. 62/312,793, dated24 Mar. 2016; and 62/312,801, dated 24 Mar. 2016.

FIELD

The present disclosure relates to improvements in production ofhydrocarbon-comprising material from hydrocarbon reservoirs having lowpermeability zones.

BACKGROUND

Thermal enhanced oil recovery methods are used to recover bitumen andheavy oil from hydrocarbon reservoirs. The most dominant thermalenhanced oil recovery method being applied to oil sands reservoirs issteam-assisted gravity drainage (“SAGD”). However, SAGD performancesuffers when oil sands reservoirs include zones of reduced permeability,such as shale barriers.

SUMMARY

In one aspect, there is provided a process for producing hydrocarbonmaterial from a reservoir, comprising: cooling at least a portion of alow permeability zone within the reservoir with effect that water,disposed within the low permeability zone, freezes and expands, witheffect that one or more flow paths are formed through the lowpermeability zone; mobilizing hydrocarbon material within the reservoirsuch that the mobilized hydrocarbon material is conducted through thelow permeability zone via the one or more flow paths; and after theconduction of the mobilized hydrocarbon material through the lowpermeability zone via the one or more flow paths, producing themobilized hydrocarbon material.

In another aspect, there is provided a process for producing hydrocarbonmaterial from a reservoir, comprising: cooling at least a portion of alow permeability zone within the reservoir such that stress is reducedwithin the at least a portion of a low permeability zone; pressurizingthe cooled portion of the low permeability zone with effect that one ormore flow paths are formed through the low permeability zone; mobilizinghydrocarbon material within the reservoir such that the mobilizedhydrocarbon material is conducted through the low permeability zone viathe one or more flow paths; and after the conduction of the mobilizedhydrocarbon material through the low permeability zone via the one ormore flow paths, producing the mobilized hydrocarbon material.

In another aspect, there is provided a process for producing hydrocarbonmaterial from a reservoir, comprising: heating at least a portion of alow permeability zone within the reservoir with effect that water,disposed within the low permeability zone, vaporizes and effectsformation of one or more flow paths through the low permeability zone;mobilizing hydrocarbon material within the reservoir such that themobilized hydrocarbon material is conducted through the low permeabilityzone via the one or more flow paths; and after the conduction of themobilized hydrocarbon material through the low permeability zone via theone or more flow paths, producing the mobilized hydrocarbon material.

In another aspect, there is provided a process for producing hydrocarbonmaterial from a reservoir, comprising: heating at least a portion of alow permeability zone within the reservoir; reducing pressure of the atleast a portion of a low permeability zone, with effect that water,disposed within the low permeability zone, vaporizes and effectsformation of one or more flow paths through the low permeability zone;mobilizing hydrocarbon material within the reservoir such that themobilized hydrocarbon material is conducted through the low permeabilityzone via the one or more flow paths; and after the conduction of themobilized hydrocarbon material through the low permeability zone via theone or more flow paths, producing the mobilized hydrocarbon material.

In another aspect, there is provided a process for producing hydrocarbonmaterial from a reservoir, comprising: cooling at least a portion of alow permeability zone within the reservoir such that stress is reducedwithin the at least a portion of a low permeability zone; pressurizingthe cooled portion of the low permeability zone with effect that one ormore flow paths are formed through the low permeability zone; andreceiving hydrocarbon material, that is conducted through the one ormore of the flow paths, within a production well; and producing thereceived hydrocarbon material.

BRIEF DESCRIPTION OF DRAWINGS

Embodiments will now be described, by way of example only, withreference to the attached figures, wherein:

FIG. 1 is a schematic illustration of one side of an embodiment of asystem for implementing steam assisted gravity drainage (“SAGD”) forproducing hydrocarbon material from a reservoir having a lowpermeability zone disposed between horizontal sections of a well pair;

FIG. 2 is a schematic illustration of one side of another embodiment ofa system for implementing steam assisted gravity drainage (“SAGD”) forproducing hydrocarbon material from a reservoir having a lowpermeability zone disposed between horizontal sections of a well pair,illustrating a dimensional attribute of the low permeability zone;

FIG. 3 is a schematic illustration of an end view of the embodimentillustrated in FIG. 2;

FIG. 4 is a schematic illustration of an end view of another embodimentof a system having two well pairs for implementing steam assistedgravity drainage (“SAGD”) for producing hydrocarbon material from areservoir having a low permeability zone disposed between horizontalsections of one of the well pairs, illustrating a dimensional attributeof the low permeability zone;

FIG. 5 is a schematic illustration of one side of an embodiment of asystem for implementing steam assisted gravity drainage (“SAGD”) forproducing hydrocarbon material from a reservoir having a lowpermeability zone disposed above a horizontal section of the injectionwell of a well pair;

FIG. 6 is a schematic illustration of one side of another embodiment ofa system for implementing steam assisted gravity drainage (“SAGD”) forproducing hydrocarbon material from a reservoir having a lowpermeability zone disposed above a horizontal section of the injectionwell of a well pair, illustrating a dimensional attribute of the lowpermeability zone;

FIG. 7 is a schematic illustration of an end view of the embodimentillustrated in FIG. 6;

FIG. 8 is a schematic illustration of an end view of another embodimentof a system for implementing steam assisted gravity drainage (“SAGD”)for producing hydrocarbon material from a reservoir having a lowpermeability zone disposed above a horizontal section of the injectionwell of a well pair, illustrating a dimensional attribute of the lowpermeability zone; and

FIG. 9 is a schematic illustration of a steam chamber that has developedby operating a SAGD process using the system illustrated in any one ofFIGS. 1 to 8.

DETAILED DESCRIPTION

The present disclosure relates to use of a production-initiating fluidfor effecting production of hydrocarbon material from ahydrocarbon-containing reservoir 102 disposed within a subterraneanformation below the earth's surface 12.

As used herein, the following terms have the following meanings:

“Hydrocarbon” is an organic compound consisting primarily of hydrogenand carbon, and, in some instances, may also contain heteroatoms such assulfur, nitrogen and oxygen.

“Hydrocarbon material” is material that consists of one or morehydrocarbons.

“Heavy hydrocarbon material” is material that consists of one or moreheavy hydrocarbons. A heavy hydrocarbon is a hydrocarbon that, atconditions existing with the hydrocarbon-containing reservoir, has a anAPI gravity of less than 26 degrees and a viscosity of greater than20,000 centipoise. An exemplary heavy hydrocarbon material is bitumen.

A well, or sections of a well, can be characterized as “vertical” or“horizontal” even though the actual axial orientation can vary from truevertical or true horizontal, and even though the axial path can tend to“corkscrew” or otherwise vary. The term “horizontal”, when used todescribe a section of a wellbore, refers to a horizontal or highlydeviated wellbore section as understood in the art, such as, forexample, a wellbore section having a longitudinal axis that is between70 and 110 degrees from vertical.

The meaning of the terms “above” and “below” are not intended to belimited to mean, respectively, “directly above” and “directly below”,but are rather intended to define the elevation of one or more elementsrelative to the elevation of one or more other elements.

Referring to FIGS. 1 to 8, there is provided a system 100 for carryingout a process for producing hydrocarbon material from ahydrocarbon-containing reservoir 102. In some embodiments, for example,the hydrocarbon-containing reservoir includes an oil sands reservoir,and the hydrocarbon material includes heavy hydrocarbon material, suchas bitumen.

The system 100 includes a well pair 101. The well pair 101 includes apair of wells 104, 106. Each one of the wells 104, 106, independently,includes a respective horizontal section. The well 104 functions as ainjection well and the well 106 functions as a production well. Theinjection well 104 injects production-initiating fluid to effectproduction of the hydrocarbon material via the production well 106.

In some embodiments, for example, a production-initiating fluid isinjected via an injection string 112 that is disposed within theinjection well 104, and the produced fluid is produced via a productionstring 114 that is disposed within the production well 106.

In some embodiments, for example, the injection string 112 includes aplurality of ports 112A for injecting production-initiating fluid, thatis being conducted by the injection string, into the reservoir 102 at aplurality of injection points 104A within the reservoir 102. In someembodiments, for example, the plurality of injection points 104A aredisposed along a reservoir interface 102A that defines the interfacebetween the injection well 104 and the reservoir 102. In someembodiments, for example, the ports 112A are defined within a slottedliner of the injection string 112. In some embodiments, for example, theports 112A are disposed within a horizontal section of the injectionwell 104.

In some embodiments, for example, the production string 114 includes aplurality of ports 114A for receiving fluid that is being conductedwithin the reservoir 102 in response to the injection of theproduction-initiating fluid. In some embodiments, for example, the ports114A are defined within a slotted liner of the production string 114. Insome embodiments, for example, the ports 114A are disposed within ahorizontal section of the production well 106.

A hydrocarbon production process may be implemented via the well pair101, so long as fluid communication is effected between the wells 104,106 via a communication zone 110 (i.e. fluid is conductible (forexample, by flowing)) such that the injected production-initiating fluideffects mobilization of the hydrocarbon material within the reservoir,and the mobilized hydrocarbon material is conducted to the productionwell 106 via the communication zone 110 for production via theproduction well 106. The conduction of the hydrocarbon material to theproduction well 106 is effected in response to an applied driving force(for example, application of a fluid pressure differential, or gravity,or both). In some embodiments, for example, the production-initiatingfluid functions as a drive fluid effecting conduction (or transport) ofhydrocarbon material to the production well 106. In some embodiments,for example, the production-initiating fluid functions as a heattransfer fluid, supplying heat to the hydrocarbon material, such thatviscosity of the hydrocarbon material is sufficiently reduced (in suchstate, the hydrocarbon material is said to be mobilized), such that thehydrocarbon material may be conducted to the production well 106 by adriving force, such as, for example, a pressure differential or gravity.In some embodiments, for example, the production-initiating fluidfunctions as both a drive fluid and a heating fluid. In someembodiments, for example, the hydrocarbon material is produced alongwith some of the injected production-initiating fluid, such as, forexample, production-initiating fluid that has heated the hydrocarbonmaterial (as described above) and has become condensed, such that fluidthat is being produced via the production well includes hydrocarbonmaterial and condensed production-initiating fluid. While the wells 104,106 are disposed in fluid communication through the communication zone110, production-initiating fluid is injected into the reservoir 102 suchthat the hydrocarbon material is conducted to the well 106, via thecommunication zone 110, and produced through the well 106. In someembodiments, for example, the hydrocarbon material that is received bythe well 106 is produced via the well 106 by artificial lift. In someembodiments, for example, the producing of the hydrocarbon material viathe production well 106 is effected while the production-initiatingfluid is being injected by the injection well 104. In this respect, insome embodiments, for example, the hydrocarbon production process is acontinuous process.

In some embodiments, for example, the hydrocarbon production processincludes a thermally-actuated gravity drainage-based hydrocarbonproduction process that is implemented via the well pair 101. In suchembodiments, the horizontal section of the well 104 is vertically spacedfrom the horizontal section of the well 106, such that the horizontalsection of the well 104 is disposed above the horizontal section of thewell 106, such as, for example, by at least three (3) metres, such as,for example, by at least five (5) metres. In some embodiments, forexample, the production-initiating fluid includes steam. A productionphase (i.e. when hydrocarbon material is being produced via the well106) of the thermally-actuated gravity drainage-based hydrocarbonproduction process occurs after the communication zone 110 has beenestablished. The establishing of the communication zone 110 includes atleast the establishing of interwell communication, through the interwellregion 108, between the wells 104, 106. “Interwell communication”, inthe context of a thermally-actuated gravity drainage-based hydrocarbonproduction process, describes a condition of the reservoir which permitshydrocarbon material within the reservoir 102, mobilized by heatsupplied from the injected production-initiating fluid that is injectedvia the injection well 104, to be conducted, by at least gravitydrainage, to the production well 106. In this respect, the interwellcommunication is established when the injected production-initiatingfluid is able to communicate heat to hydrocarbon material within thereservoir such that the hydrocarbon material is mobilized, and themobilized hydrocarbon material is then conducted, by at least gravity,through the interwell region 108, to the production well 106.

With respect to thermally-actuated gravity drainage-based hydrocarbonproduction processes being implemented via the well pair 101, in some ofthese embodiments, for example, initially, the reservoir 102 hasrelatively low fluid mobility (such as, for example, due to the factthat the hydrocarbon material within the reservoir 102 is highlyviscous) such that the communication zone 110 is not present. In orderto enable the injected production-initiating fluid (being injectedthrough the injection well 104) to promote the conduction of thereservoir hydrocarbons, within the reservoir 102, to the production well106, the communication zone 110 must be established. This establishingof the communication zone 110 includes establishing interwellcommunication between the wells 104, 106 through the interwell region108. By establishing the interwell communication, the conduction of themobilized hydrocarbon material, through the interwell region 108, isenabled such that the mobilized hydrocarbon material is collected withinthe production well 106. The interwell communication may be establishedduring a “start-up” phase of the thermally-actuated gravitydrainage-based hydrocarbon production process. In some embodiments, forexample, during the start-up phase, the interwell region 108 is heated.In some embodiments, for example, the heat is supplied to the interwellregion 108 by effecting circulation of a start-up phase fluid (such assteam, or a fluid including steam) in one or both of the wells 104, 106.The heat that is supplied to the interwell region 108 heats thereservoir hydrocarbons within the interwell region 108, thereby reducingthe viscosity of the reservoir hydrocarbons. Eventually, the interwellregion 108 becomes heated to a temperature such that the hydrocarbonmaterial is sufficiently mobile (i.e. the hydrocarbon material has been“mobilized”) for displacement to the production well 106 by at leastgravity drainage. In this respect, eventually, sufficient hydrocarbonmaterial becomes mobilized, such that this space (the interwell region108), previously occupied by immobile, or substantially immobile,hydrocarbon material, is disposed to communicate fluid between theinjection well 104 and the production well 106 in response to a drivingforce, such that at least hydrocarbon material is conductible throughthis space in response to the driving force. Upon the interwell regionbecoming disposed to communicate fluid between the injection well 104and the production well 106 in response to a driving force, such that atleast hydrocarbon material is conductible through this space in responseto the driving force, the interwell communication, between the wells104, 106, is said to have become established. The development of thisinterwell communication signals completion of the start-up phase andconversion to a production phase.

During the production phase of a thermally-actuated gravitydrainage-based hydrocarbon production process, the communication zone110 effects fluid communication between the production-initiating fluid,being injected through the injection well 104, with hydrocarbon materialwithin the reservoir, such that the injected production-initiating fluidis conducted through the communication zone 110 and becomes disposed inheat transfer communication with hydrocarbon material within thereservoir such that the hydrocarbon material becomes heated. Whensufficiently heated such that its viscosity becomes sufficientlyreduced, the hydrocarbon material becomes mobilized, and, in thisrespect, the hydrocarbon material is able to be conducted, by at leastgravity drainage (the conduction may also, for example, be promoted by apressure differential that is established between the injectedproduction initiating fluid and the production well 106, which may also,in some embodiments, be characterized as a “drive process” mechanism),through the communication zone 110, to the production well 106, andsubsequently produced from the production well 106 by artificial lift,such as by a pump. During the production phase, while theproduction-initiating fluid is being injected into the communicationzone 110 via the injection well 104, as the mobilized hydrocarbonmaterial drains to the production well 106, space previously occupied bythe hydrocarbon material within the reservoir becomes occupied by theinjected production-initiating fluid, thereby exposing a freshhydrocarbon material surface for receiving heat from theproduction-initiating fluid (typically, by conduction). This repeatedcycle of heating, mobilization, drainage, and establishment of heattransfer communication between the production-initiating fluid and afreshly exposed hydrocarbon material source results in the growth of thecommunication zone 110, with the freshly exposed hydrocarbon materialbeing disposed along an edge of the communication zone 110. Referring toFIG. 9, in some embodiments, for example, the communication zone 110includes a “vapour chamber”. In some embodiments, for example, thevapour chamber may also be referred to as a “steam chamber”. In someembodiments, for example, the growth of the communication zone 110 isupwardly, laterally, or both, and, typically, extends above thehorizontal section of the injection well 104.

In some embodiments, for example, where, in implementing thethermally-actuated gravity drainage-based hydrocarbon productionprocess, the production-initiating fluid includes steam, the processthat is effecting this production is described as “steam-assistedgravity drainage” or “SAGD”. In some embodiments, for example, thecommunication zone 110 includes a vapour chamber, such as, for example,a “steam chamber”. During SAGD, the conduction of the mobilizedhydrocarbon material to the production well 106 is accompanied bycondensed steam (i.e. water), whose condensation is effected by at leastheat loss to the hydrocarbon material (which effects the mobilization ofthe hydrocarbon material).

In some embodiments, for example, the reservoir includes a lowpermeability zone. The low permeability zone 116 is a zone whoseabsolute permeability is less than 1000 millidarcies, such as, forexample, less than 100 millidarcies, such as, for example, less than 10millidarcies.

Examples of low permeability zones 116 include baffles and barriers.These include barrier or baffle layers of shale, breccia, inclinedheterolithic strata, mud, and mudstone. It will be understood that suchlayers are formed by natural geological activity and can be of variousshapes and configuration disposed above, below or between the injectionwell 104 and the production well 106. In the drawings, the lowpermeability zones 116 are shown as simple geometric shapes forsimplicity of explanation only and those skilled in the relevant artwill recognize that great variations in shape, configuration andpermeability will exist in such naturally formed geological layers.

In some embodiments, for example, the low permeability zone 116 has adimension of at least 10 metres, such as, for example, 25 metres, suchas, for example, at least 35 metres. In some embodiments, for example,the dimension is a width.

In some embodiments, for example, the low permeability zone 116 isrelatively thin, and, in this respect, in some embodiments, for example,is characterized by a maximum thickness of less than 5 centimetres.

In some embodiments, for example, at least a continuous portion of thelow permeability zone 116 is disposed within a horizontal plane withinthe reservoir 102, wherein the horizontal plane-disposed continuousportion of the low permeability zone 116 is characterized by an area ofat least 100 square metres.

In some embodiments, for example, the low permeability zone 116 isdisposed between the horizontal sections of the wells 104, 106, such as,for example, in the interwell region 108.

Referring to FIGS. 2 and 3, in some embodiments, for example, at least acontinuous portion of the low permeability zone 116 is disposed betweenthe horizontal sections of the wells 104, 106, and the continuousportion has an axis “A1”, and the axis “A1” has a length “L1” of atleast 10 metres, such as, for example, at least 50 metres, such as, forexample, at least 100 metres.

Referring to FIG. 4, in some embodiments, for example, at least acontinuous laterally-extending portion of the low permeability zone 116is disposed between the horizontal sections of the wells 104, 106 and isalso extending towards another well pair 201 and across at least ⅓ of aspacing distance “SD” between the well pairs 101, 102. In someembodiments, for example, the at least a continuous laterally-extendingportion of the low permeability zone 116 extends from between the wellpair 101 and towards the another well pair 201 by a distance “D1” of atleast 25 metres, such as, for example, at least 35 metres.

Referring to FIG. 5, in some embodiments, for example, the lowpermeability zone 116 is disposed above both of the horizontal sectionsof the wells 104, 106.

Referring to FIGS. 6 and 7, in some embodiments, for example, at least acontinuous portion of the low permeability zone 116 includes an axis“A2”, and the axis “A2” of the at least a continuous portion is disposedabove, and in vertical alignment with, a longitudinal axis “A3” of thehorizontal section of the well 104, and has a length “L2” of at least 10metres, such as, for example, at least 50 metres, such as, for example,at least 100 metres.

Referring to FIG. 8, in some embodiments, for example, at least acontinuous portion of the low permeability zone 116 is disposed abovethe horizontal section of the well 104 and at a height “H”, above thebottom of the reservoir, that is less than 50% of the total height “TH”of the reservoir. In some embodiments, for example, at least acontinuous portion of the low permeability zone 116 is disposed abovethe horizontal section of the well 104 and at a height “H” of less than35 metres (such as, for example, less than 25 metres) above the bottomof the reservoir.

There is provided a process for forming a flow path within a lowpermeability zone 116, for effecting flow communication within thereservoir 102, via the flow path, between a communication-interferedzone 118A and a wellbore. The low permeability zone 116 is disposedbetween the wellbore and the communication-interfered zone 118A. In someembodiment, for example, the low permeability zone 116 functions as animpediment for conduction of fluid material into and from thecommunication-interfered zone 118A and a wellbore, and the flowcommunication effected by the flow path is intended to enable suchconduction. In some embodiments, for example, the impediment includes animpediment to a vertical flow of fluid. In some embodiments, forexample, the wellbore is defined as an injection well 104 of a SAGDsystem. In some embodiments, for example, the wellbore is defined as aproduction well 106 of a SAGD system.

In some embodiments, for example, the process for forming a flow pathwithin a low permeability zone 116 includes cooling of at least aportion of the low permeability zone 116.

In some embodiments, for example, the cooling of the at least a portionof the low permeability zone 116 is such that the rate of decrease oftemperature within the at least a portion of the low permeability zone116 is at least one (1) degrees Celsius per hour, such as, for example,at least two (2) degrees Celsius per hour.

In some embodiments, for example, the cooling is effected by injecting acold fluid (i.e. a fluid having a temperature that is less than thetemperature of the low permeability zone) with effect that the injectedcold fluid becomes disposed in thermal communication with the lowpermeability zone 116. In some embodiments, for example, the injectingincludes circulating a cold fluid within one or both of the wells 104,106, in which case, the cooling is effected by conduction of heat fromthe subterranean formation between the injection well 104 and the lowpermeability zone 116. In some embodiments, for example, the lowpermeability zone 116 is spaced apart from at least one of the wells104, 106, through which the cold fluid is being circulated, by a minimumdistance of less than 15 metres, such as, for example, less than 10metres.

The low permeability zone 116 as referred to herein is the barrier thatintended to be fractured or broken in order to allow bitumen and fluidsto pass through the zone 116 along fractures. The cooled or frozenregion of the reservoir extends from the injection well 104 (i.e. theupper well 104 in the injection-production well 104, 106 pair throughwhich cold fluid is circulated in order to cool or freeze the formation)into the formation to a distance that is dependent on the length of timeof cooling, the temperature of the cooling fluid and the thermalconductivity of the formation. The entire cooled or frozen region of thereservoir extends further than merely into the low permeability zone 116(i.e. shale or low permeability barrier) but always includes the shaleor permeability barrier 116. The cold fluid injected into the reservoirvia the injection well 104 creates a cooled region that ideally extendssome distance above and below the low permeability zone 116 (shalebarrier). In the case where the low permeability zone 116 (shale) islocated above the injector well 104, there exists a warmer reservoirzone above the cooled zone (which includes the low permeability zone116) located between the cap rock of the reservoir and the cooled zone.Thus it is in this warmer zone of the reservoir that the originaltemperature of the reservoir is maintained and is not effected bycooling. It is in the warmer zone that is beyond the range of coolingthat the upward propagation of the fracture is be truncated or impededfrom forming. The truncation of fractures in the warmer zone of thereservoir allows higher pressures to be used in the injection well 104because the fracturing of the cap rock layer and resultant escape ofcooling fluid, gas or bitumen is also impeded.

In some embodiments, for example, the temperature of the cold fluid isless than minus 50 degrees Celsius.

In some embodiments, for example, the rate of cooling of the at least aportion of the low permeability zone 116 is at least 0.03 degreesCelsius per metre per day, such as, for example, 0.04 degrees Celsiusper metre per day.

In some embodiments, for example, the cold fluid includes any one, orany combination of, the fluids selected from the group consisting of:liquid nitrogen, liquid CO2 and liquid hydrocarbon solvents such aspropane, butane, and natural gas condensate.

In some embodiments, for example, the cooling of the low permeabilityzone 116 is effected prior to the production phase. In some embodiments,for example, the cooling of the low permeability zone 116 is effectedprior to the heating of the interwell region 108 during the SAGDstart-up phase. In this respect, in some embodiments, for example, afterthe cooling, a SAGD start-up phase is implemented, followed by a SAGDproduction phase.

Cooling of the low permeability zone 116 relieves stresses within thelow permeability zone 116. Because the heat sink is within a wellthrough which cold fluid is being conducted, as a necessary incident,such cooling also relieves the stresses in an intermediate region of thesubterranean formation, between a well through which cold fluid is beingconducted (e.g. the injection well) 104 and the low permeability zone116, thereby conditioning the low permeability zone 116, as well as theintermediate formation region between the well and the low permeabilityzone 116, such that both of the intermediate formation region and thelow permeability zone 116 are disposed for crack formation at lowerapplied pressures.

In some embodiments, for example, the cooling of the low permeabilityzone 116 is with effect that a temperature decrease is effected to atleast a portion of the low permeability zone 116, and with effect thatone or more cracks are formed within the low permeability zone 116.

In some embodiments, for example, the cooling of the low permeabilityzone 116 is with effect that a temperature decrease is effected to atleast a portion of the low permeability zone 116 to below apredetermined temperature. In some embodiments, for example, the coolingof the low permeability zone 116 is such that at least a portion of thelow permeability zone 116 becomes disposed at a temperature that isbelow the freezing point of water at the pressure within the lowpermeability zone 116.

In this respect, in some embodiments, for example, the cooling of thelow permeability zone is with effect that at least a portion of the lowpermeability zone 116 becomes disposed at a temperature that is belowthe freezing point of water at the pressure within the low permeabilityzone and effects freezing of water within the at least a portion of thelow permeability zone. Because water expands upon freezing, one or morecracks are formed in the low permeability zone 116 in response to thefreezing of the water, thereby defining one or more flow paths (cracks)for conducting of fluid material within the low permeability zone, suchas, for example, conducting of a heating fluid (such as, for example, astart-up phase fluid or a production-initiating fluid), or conducting ofmobilized hydrocarbon material. The stresses in the cooled lowpermeability zone 116 is reduced, however stresses in the adjacentnon-cooled portions of the reservoir remain unaffected. As a consequencecrack propagation within the cooled low permeability zone 116 can beaccomplished using pressurized fluid at a lower pressure, therebyreducing energy costs and also reducing the risk of fracturing theoverlying cap rock layer. When a fracture propagates from the cooled lowpermeability zone 116 towards an adjacent warmer uncooled portion of thereservoir, the warmer portion is relatively more resistant to crack orfracture propagation since stresses are maintained at a higher level inthe warmer portion. In some embodiments, for example, the entirety ofthe low permeability zone 116 becomes disposed at a temperature that isbelow the freezing point of water at the pressure within the lowpermeability zone, in response to the cooling.

In some embodiments, for example, the process for forming a flow pathwithin a low permeability zone 116 includes cooling the low permeabilityzone 116 (such as, for example, in accordance with any one of theembodiments, as above-described), and, after the low permeability zone116 has been cooled, pressurizing the cooled low permeability zone 116.As explained above, the cooling of the low permeability zone 116relieves stresses within the low permeability zone 116, as well as anintermediate formation region between the well (which is functioning asa heat sink) and the low permeability zone 116, thereby conditioningboth of the intermediate formation region and the low permeability zone116 for crack formation at lower applied pressures. Co-operatively,pressurized material is injected into the reservoir 102, forpressurizing the cooled low permeability zone 116, and thereby effectingformation of one or more cracks within the cooled low permeability zone116. However in the adjacent warmer uncooled portion of the reservoir,the warmer portion is relatively more resistant to crack or fracturepropagation and crack propagation is terminated within the warmeruncooled portion of the reservoir, where stresses are unaffected. Theability to control crack propagation by controlling the zone that iscooled, allows the use of higher pressure fracturing fluid because therisk of fracturing and penetrating the overlying cap rock layer isreduced or eliminated. Cracks are propagated only through the cooled lowpermeability zone 116 where stresses are lowered and the warmer uncooledportion of the reservoir having higher stresses tends to resist crackpropagation thereby limiting and controlling the formation of cracksinto zones where cracks would be undesirable, such as into cap rocklayers. In some embodiments, for example, the pressurized material issupplied via a wellbore, such as the injection well 104, or theproduction well 106, or both, and injected into the reservoir 102 forpressurizing the low permeability zone 116. In some embodiments, forexample, the pressurizing is with effect that the low permeability zonebecomes disposed at a pressure of at least original reservoir pressure,such as, for example, at least 105% of original reservoir pressure, suchas, for example, at least 110% of original reservoir pressure. In someof these embodiments, for example, the pressurizing is with effect thatthe low permeability zone 116 becomes disposed at a pressure of up tothe maximum allowable pressure of the reservoir 102 (the pressure thatis determined to maintain integrity of the cap rock above the reservoir)

In some embodiments, for example, the pressurized material is injectedat an injection pressure of between the original reservoir pressure andthe maximum allowable pressure of the reservoir 102. In someembodiments, for example, the injection pressure is the lowest pressure(above the original reservoir pressure) at which formation parting isachievable following cooling of the reservoir 102 (such as, for example,in close proximity to a well, such as the injection well 104), suchcooling resulting in a reduction in reservoir effective stress from suchcooling.

In some embodiments, for example, the duration of the injecting of thepressurized material is at least two (2) minutes, such as, for example,at least five (5) minutes, such as, for example, at least 20 minutes,such as for example, at least one (1) hour, such as, for example, atleast two (2) hours, such as, for example, at least five (5) hours, suchas, for example, at least one (1) day, such, as for example, at leasttwo (2) days, such as, for example, at least five (5) days.

In some embodiments, for example, the pressurized material includes afluid. In some embodiments, for example, the pressurized materialincludes a liquid including water. In some embodiments, for example, theliquid includes water and chemical additives. In other embodiments, forexample, the pressurized material is a slurry including water, proppant,and chemical additives. Exemplary chemical additives include acids,sodium chloride, polyacrylamide, ethylene glycol, borate salts, sodiumand potassium carbonates, glutaraldehyde, guar gum and other watersoluble gels, citric acid, and isopropanol. In some embodiments, forexample, the pressurized material is supplied to effect hydraulicfracturing of the reservoir.

In some embodiments, for example, the process for forming a flow pathwithin a low permeability zone 116 includes heating the low permeabilityzone 116.

In some of these embodiments, for example, the heating is effected bycirculating a heating fluid (i.e. a fluid having a temperature that isgreater than the temperature of the low permeability zone) within one orboth of the wells 104, 106 (such as, for example, during the SAGDstart-up phase), with effect that the circulated heating fluid becomesdisposed in thermal communication with the low permeability zone 116.

In some embodiments, for example, the heating fluid includes steam, andmay also include steam admixed with a solvent that is soluble within thehydrocarbon material that is disposed within the reservoir 102. In someembodiments, for example, the heating fluid includes glycerine. In someembodiments, for example, the heating fluid includes diethanolamine(DEA). In some embodiments, for example, the heating fluid is thestart-up phase fluid. In some embodiments, for example, the lowpermeability zone 116 is spaced apart from at least one of the wells104, 106, through which the heating fluid is being circulated, by aminimum distance of less than 15 metres, such as, for example, less than10 metres.

In some embodiments, for example, the heating is effected by injecting(such as, for example, during the SAGD production phase) a heating fluid(i.e. a fluid having a temperature that is greater than the temperatureof the low permeability zone) into the reservoir 102 with effect thatthe injected heating fluid becomes disposed in thermal communicationwith the low permeability zone 116. In some of these embodiments, forexample, the thermal communication is established by mobilizinghydrocarbon material between the injection well 104 and the lowpermeability zone 116 (such as by, for example, implementing theproduction phase of the thermally-actuated gravity drainage-basedprocess, as above-described) such that the mobilized hydrocarbonmaterial is conducted to the production well 106, and the spacepreviously occupied by immobile, or substantially immobile, hydrocarbonmaterial, is disposed to conduct the injected heating fluid from one orboth of the wells 104, 106, such that the injected heating fluid becomesdisposed in thermal communication with the low permeability zone 116. Insome embodiments, for example, the heating fluid includes steam, and mayalso include steam admixed with a solvent that is soluble within thehydrocarbon material that is disposed within the reservoir. In someembodiments, for example, the heating fluid is the production-initiatingfluid. In some embodiments, for example, the low permeability zone 116is spaced apart from at least one of the wells 104, 106, through whichthe heating fluid is being injected, by a minimum distance of less than15 metres, such as, for example, less than 10 metres.

In some embodiments, for example, the heating of the low permeabilityzone 116 includes heating that is effected by electrical heating. Insome embodiments, for example, the electrical heating can be effected bya resistive electric heater or by electromagnetic energy propagationinto the formation. In some embodiments, for example, the electricalheating is effected by an electrical heater disposed in one or both ofthe wells 104, 106. In some embodiments, for example, the lowpermeability zone 116 is spaced apart from at least one of the wells104, 106, through which the electrical heater is disposed, by a minimumdistance of less than 15 metres, such as, for example, less than 10metres.

In some embodiments, for example, the heating of the low permeabilityzone 116 includes heating that is effected by in-situ combustion. Anexemplary in-situ combustion process is SAGDOX™.

In some embodiments, for example, the heating of the low permeabilityzone 116 is effected prior to the SAGD production phase. In someembodiments, for example, the heating of the low permeability zone 116is effected after hydrocarbon material has been produced during the SAGDproduction phase.

In some embodiments, for example, the heating of the low permeabilityzone 116 is effected prior to the heating of the interwell region 108during the SAGD start-up phase.

In some embodiments, for example, the heating of the low permeabilityzone 116 is effected during the heating of the interwell region 108during the SAGD start-up phase, in which case, in some embodiments, forexample, the heating fluid includes the start-up phase fluid.

In some embodiments, for example, the heating of the low permeabilityzone 116 is effected during the SAGD production phase, in which case, insome embodiments, for example, the heating fluid includesproduction-initiating fluid.

In some embodiments, for example, the heating of the low permeabilityzone 116 is with effect that a temperature increase is effected to atleast a portion of the low permeability zone 116, and with effect thatone or more cracks are formed within the low permeability zone 116. Insome embodiments, for example, the heating of the low permeability zone116 is with effect that a temperature increase is effected to at least aportion of the low permeability zone 116 to above a predeterminedtemperature. In some embodiments, for example, the heating of the lowpermeability zone 116 is such that at least a portion of the lowpermeability zone 116 becomes disposed at a temperature of at leaststeam temperature at the pressure within the low permeability zone 116.By heating the low permeability zone 116 such that at least a portion ofthe low permeability zone 116 becomes disposed at a temperature of atleast steam temperature at the pressure within the low permeability zone116, water within the low permeability zone 116 is vaporized, expands,and effects crack formation within the low permeability zone.

In some embodiments, for example, the rate of heating necessary toeffect mechanical failure within the low permeability zone 116, andconsequent crack formation, is dependent on the permeability of the lowpermeability zone 116: the lower the permeability, the low the rate ofheating that is required. This is because the fluid (in someembodiments, for example, a fluid including water), being vaporizedwithin the low permeability zone 116, will escape from the lowpermeability zone 116 at a rate that is fast enough such that pressureincrease within the low permeability zone 116 is not sufficient toeffect mechanical failure and consequent crack formation. In thisrespect, with zones of lower permeability (such as for low permeabilityzones with permeability less than 5 millidarcies), a faster rate ofheating is required to enable a pressure increase within the lowpermeability zone 116 that is sufficient to effect mechanical failureand consequent crack formation. In some embodiments, for example, theheating of the at least a portion of the low permeability zone 116 issuch that the rate of increase of temperature within the at least aportion of the low permeability zone 116 is at least one (1) degreesCelsius per hour, such as, for example, at least two (2) degrees Celsiusper hour.

In some embodiments, for example, the duration of the heating is atleast one (1) minute, such as, for example, at least two (2) minutes,such as, for example, at least five (5) minutes, such as, for example,at least ten (10) minutes, such as, for example, at least one (1) hour,such as, for example, at least five (5) hours, such as, for example, atleast one (1) day, such as, for example, at least two (2) days, such as,for example, at least five (5) days. In some embodiments, for example,the duration of the heating of the at least a portion of the lowpermeability zone 116 is at least 30 days. In some embodiments, forexample, the duration of the heating of the at least a portion of thelow permeability zone 116 is between 30 days and 90 days. The durationdepends on the distance of the at least a portion of the lowpermeability zone 116 from the heat source.

In some embodiments, for example, the process for forming a flow pathwithin a low permeability zone 116 includes heating the low permeabilityzone 116 (such as, for example, in accordance with any one of theembodiments, as above-described), and, after the low permeability zone116 has been heated, effecting a reduction in pressure of the heated lowpermeability zone 116. The heating of at least a portion of the lowpermeability zone 116, and after the heating, the effecting a reductionin pressure of the low permeability zone 116, co-operate with effectthat water within the low permeability zone 116 is vaporized, expands,and effects crack formation within the low permeability zone 116.

The rate of heating necessary to cause mechanical failure of the lowpermeability zone and the formation of cracks is dependent on thepermeability of the low permeability zone, the lower the permeability,the lower the rate of heating required. This is because the fluid beingvaporized within the low permeability zone, in some instances water,will escape from the low permeability zone and not cause the pressure toincrease enough to result in formation of cracks. For low permeabilityzones with permeability less than 5 millidarcies, a rate of heating ofat least one degree Celsius per hour is required, and rates higher, suchas 2° C./hr would be preferred. In some embodiments, for example, theheating of the at least a portion of the low permeability zone 116 issuch that the rate of increase of temperature within the at least aportion of the low permeability zone 116 is at least one (1) degreesCelsius per hour, such as, for example, at least two (2) degrees Celsiusper hour. The temperature of the low permeability zone must reach thesaturated steam temperature at the reservoir pressure so that liquidwater contained within the low permeability zone will begin to vaporizeimmediately as the pressure is reduced.

In some embodiments, for example, the heating of at least a portion ofthe low permeability zone 116 is with effect that the temperature of theat least a portion of the low permeability zone 116 is between 200degrees Celsius and 240 degrees Celsius.

In some embodiments, for example, the duration of the heating is atleast one (1) minute, such as, for example, at least two (2) minutes,such as, for example, at least five (5) minutes, such as, for example,at least ten (10) minutes, such as, for example, at least one (1) hour,such as, for example, at least five (5) hours, such as, for example, atleast one (1) day, such as, for example, at least two (2) days, such as,for example, at least five (5) days. In some embodiments, for example,the duration of the heating of the at least a portion of the lowpermeability zone 116 is at least 30 days. In some embodiments, forexample, the duration of the heating of the at least a portion of thelow permeability zone 116 is between 30 days and 90 days. The durationdepends on the distance of the at least a portion of the lowpermeability zone 116 from the heat source.

After the temperature increase has been effected by the heating, areduction in pressure of the low permeability zone 116 is effected. Thereduction in pressure is with effect that vaporized water is produced,and such vaporized water is derived from water within the lowpermeability zone 116. The produced vaporized water is disposed at asufficient pressure to induce sufficient stress within the rock of thelow permeability zone 116 to effect formation of one or more crackswithin the low permeability zone 116. In some embodiments, for example,the rate at which the pressure reduction is effected is a function ofthe permeability of the low permeability zone 116.

In some embodiments, for example, the reduction in pressure is at least50 psi over a period of time of 48 hours, such as, for example, at least100 psi over a period of time of 48 hours.

When the heating is effected by the circulating of heating fluid withinone or both of the wells 104, 106 (such as, for example, during the SAGDstart-up phase), in some of these embodiments, for example, thereduction in pressure of the low permeability zone 116 is effected bysuspending the circulation of the heating fluid.

When the heating is effected by electrical heating, in some of theseembodiments, for example, the reduction in pressure of the lowpermeability zone 116 is effected by producing hydrocarbon material viaone or both of the wells 104, 106.

When the heating is effected by injecting of heating fluid into thereservoir 102, in some of these embodiments, for example, the reductionin pressure of the low permeability zone 116 is effected by suspendingsupplying of the heating fluid into the communication zone 110.

When the heating is effected by injecting (such as, for example, via theinjection well 104) of heating fluid (such as, for example,production-initiating fluid) into the reservoir 102 (such as, forexample, the communication zone 110), while producing fluid (in someembodiments, for example, the fluid includes hydrocarbon material) fromthe reservoir 102 (such as, for example, from the communication zone110, and via the well 106), in some of these embodiments, for example,the reduction in pressure of the low permeability zone 116 is effectedby increasing the rate of production of fluid from the reservoir 102,while continuing the injecting of the heating fluid to the reservoir 102at the same or substantially the same molar rate.

When the heating is effected by injecting (such as, for example, via theinjection well 104) of heating fluid (such as, for example,production-initiating fluid) into the reservoir 102 (such as, forexample, the communication zone 110), while producing fluid (in someembodiments, for example, the fluid includes hydrocarbon material) fromthe reservoir 102 (such as, for example, from the communication zone110, and via the well 106), in some of these embodiments, for example,the reduction in pressure of the low permeability zone 116 is effectedby continuing production of fluid from the reservoir 102 at the same orsubstantially the same rate, while decreasing the rate at which theheating fluid is supplied to the reservoir 102.

When the heating is effected by injecting (such as, for example, via theinjection well 104) of heating fluid (such as, for example,production-initiating fluid) into the reservoir 102 (such as, forexample, the communication zone 110), while producing fluid (in someembodiments, for example, the fluid includes hydrocarbon material) fromthe reservoir 102 (such as, for example, from the communication zone110, and via the well 106), in some of these embodiments, for example,the reduction in pressure of the low permeability zone 116 is effectedby, co-operatively, modulating the rate at which the heating fluid issupplied to the reservoir 102 and modulating the rate at which fluid isproduced from the reservoir 102. In this respect, the modulating of therate at which the heating fluid is supplied to the reservoir 102 and themodulating the rate at which fluid is produced from the reservoir 102co-operate with effect that the reduction in pressure of the lowpermeability zone 116 is effected.

In some embodiments, for example, the process for forming a flow pathwithin a low permeability zone 116 is effected in response to detectionof the low permeability zone 116. In some of these embodiments, forexample, such detection is effected only after the SAGD start-up phasehas commenced and prior to the SAGD production phase. In someembodiments, for example, such detection is effected only after the SAGDproduction phase has commenced. In some embodiments, for example, thedetection of the low permeability zone 116 is inferred from temperatureconformance data, drilling logs, or petrophysical logs.

In some embodiments, for example, the low permeability zone 116 isdisposed within the interwell region 108 (between the horizontalsections of the wells 104, 106), with effect that acommunication-interfered zone 118A is disposed between the lowpermeability zone 116 and the horizontal section of the production well106, and a communication-interfered zone 118B is disposed between thelow permeability zone 116 and the horizontal section of the injectionwell 104. The low permeability zone 116 is disposed for at leastinterfering with fluid communication, and, in some embodiments, forblocking flow communication, between: (i) the injection well 104 and thecommunication-interfered zone 118A, and (ii) the production well 106 andthe communication-interfered zone 118B. In this respect, the lowpermeability zone 116 is disposed for at least interfering with, and insome embodiments, blocking, conduction of fluid material between: (i)the injection well 104 and the communication-interfered zone 118A, and(ii) the production well 106 and the communication-interfered zone 118B,and, therefore, functions as a vertical impediment to such conduction.

During the start-up phase, the low permeability zone 116 is disposed forat least interfering with, and in some embodiments, blocking, conductionof heat from start-up phase fluid, that is being circulated by the wells104, 106, to the communication-interfered zones 118A, 118B, thereby atleast interfering with mobilization of the hydrocarbon material withinthe communication-interfered zones 118A, 118B by the start-up phasefluid. Also during the start-up phase, the low permeability zone 116 isdisposed for at least interfering with, and in some embodiments,blocking, conduction of mobilized hydrocarbon material from thecommunication-interfered zone 118B to the production well 106, andthereby impeding the development of a flow-communicating space (i.e.interwell communication), that has been previously occupied by immobile,or substantially immobile, hydrocarbon material, for communicating flowbetween the injection well 104 and the production well 106 in responseto a driving force, such that at least hydrocarbon material isconductible through this space in response to the driving force (i.e.interwell communication). During the production phase, the lowpermeability zone 116 is disposed for at least interfering with, and insome embodiments, blocking, conduction of the mobilized hydrocarbonmaterial that is draining towards the production well 106 from thevapour (e.g. steam) chamber, via the communication-interfered zone 118B,and thereby interfering with production.

The one or more cracks that are formed, in accordance with any one ofthe processes described above, effect flow communication through the lowpermeability zone 116, enabling conduction of fluid material within theinterwell region 108 via the low permeability zone 116. In this respect,in some embodiments, for example, the crack formation is with effectthat there is an increase in absolute permeability of the lowpermeability zone 116 by at least 200%, such as, for example, by atleast 2500%, such as, for example, at least 5000%.

In this respect, the one or more cracks can effect: (i) conduction ofstart-up phase fluid from the well 104 to the communication-interferedzone 118A, or (ii) conduction of start-up phase fluid from the well 106to the communication-interfered zone 118B, or both of (i) and (ii),thereby facilitating heating of one or both of thecommunication-interfered zones 118A, 118B, during the start-up phase.Also, the one or more cracks can effect conduction of mobilizedhydrocarbon material from the communication-interfered zone 118B to thewell 106, during the start-up phase, thereby facilitating theestablishment of interwell communication, as above-described. Further,the one or more cracks can effect conduction of mobilized hydrocarbonsfrom the communication-interfered zone 118B to the well 106 during theproduction phase, thereby facilitating an increased rate of productionof hydrocarbon material from the reservoir.

In some embodiments, for example, the low permeability zone 116 isdisposed above the horizontal sections of the injection well 104, and,therefore, above the horizontal section of the production well (see FIG.5), with effect that the low permeability zone 116 is disposed between acommunication-interfered zone 1182 and the horizontal section of theproduction well 106, and also between the communication interfered zone1182 and the horizontal section of the injection well 104. In thisrespect, the low permeability zone 116 is disposed for at leastinterfering with flow communication, and, in some embodiments, forblocking flow communication, between: (i) the injection well 104 and thecommunication-interfered zone 1182, and (ii) the production well 106 andthe communication-interfered zone 1182. In this respect, the lowpermeability zone 116 is disposed for at least interferes with, and insome embodiments, blocking, conduction of fluid material between: (i)the injection well 104 and the communication-interfered zone 1182, and(ii) the production well 106 and the communication-interfered zone 1182,and, therefore, functions as a vertical impediment to such conduction.

During the production phase, the low permeability zone 116 is disposedfor at least interfering with, and in some embodiments, blocking,conduction of the production-initiating fluid to thecommunication-interfered zone 1182 (disposed above the low permeabilityzone 116) for effecting heating and mobilization of hydrocarbon materialdisposed within the communication-interfered zone 1182. In this respect,in some embodiments, for example, the low permeability zone 116functions as an impediment to the growth of the vapor (or steam)chamber. As well, even if the production-initiating fluid is able tomigrate above the low permeability zone 116 and into thecommunication-interfered zone 1182, the low permeability zone 116 isdisposed for at least interfering with, and in some embodiments,blocking, conduction of the mobilized hydrocarbon material that isdraining from the communication-interfered zone 1182 (e.g. the steamchamber) to the production well 106, and thereby interfering withproduction.

In this respect, the one or more cracks, that are formed in accordancewith any one of the processes described above, can effect conduction ofthe production-initiating fluid from the injection well 104 to thecommunication-interfered zone 1182 during the production phase, therebyfacilitating mobilization of the hydrocarbon material within thereservoir, and enabling growth of the vapour (e.g. steam) chamber. Also,the one or more cracks can effect conduction of the mobilizedhydrocarbons from the communication-interfered zone 1182 to theproduction well 106 during the production phase, thereby facilitating anincreased rate of production of hydrocarbon material from the reservoir.

In the above description, for purposes of explanation, numerous detailsare set forth in order to provide a thorough understanding of thepresent disclosure. However, it will be apparent to one skilled in theart that these specific details are not required in order to practicethe present disclosure. Although certain dimensions and materials aredescribed for implementing the disclosed example embodiments, othersuitable dimensions and/or materials may be used within the scope ofthis disclosure. All such modifications and variations, including allsuitable current and future changes in technology, are believed to bewithin the sphere and scope of the present disclosure. All referencesmentioned are hereby incorporated by reference in their entirety.

1. A process for producing hydrocarbon material from a reservoir,comprising: cooling at least a portion of a low permeability zone withinthe reservoir with effect that water, disposed within the lowpermeability zone, freezes and expands, with effect that one or moreflow paths are formed through the low permeability zone; mobilizinghydrocarbon material within the reservoir such that the mobilizedhydrocarbon material is conducted through the low permeability zone viathe one or more flow paths; and after the conduction of the mobilizedhydrocarbon material through the low permeability zone via the one ormore flow paths, producing the mobilized hydrocarbon material.
 2. Aprocess for producing hydrocarbon material from a reservoir, comprising:cooling at least a portion of a low permeability zone within thereservoir such that stress is reduced within the at least a portion of alow permeability zone; pressurizing the cooled portion of the lowpermeability zone with effect that one or more flow paths are formedthrough the low permeability zone; mobilizing hydrocarbon materialwithin the reservoir such that the mobilized hydrocarbon material isconducted through the low permeability zone via the one or more flowpaths; and after the conduction of the mobilized hydrocarbon materialthrough the low permeability zone via the one or more flow paths,producing the mobilized hydrocarbon material.
 3. A process for producinghydrocarbon material from a reservoir, comprising: heating at least aportion of a low permeability zone within the reservoir with effect thatwater, disposed within the low permeability zone, vaporizes and effectsformation of one or more flow paths through the low permeability zone;mobilizing hydrocarbon material within the reservoir such that themobilized hydrocarbon material is conducted through the low permeabilityzone via the one or more flow paths; and after the conduction of themobilized hydrocarbon material through the low permeability zone via theone or more flow paths, producing the mobilized hydrocarbon material. 4.A process for producing hydrocarbon material from a reservoir,comprising: heating at least a portion of a low permeability zone withinthe reservoir; reducing pressure of the at least a portion of a lowpermeability zone, with effect that water, disposed within the lowpermeability zone, vaporizes and effects formation of one or more flowpaths through the low permeability zone; mobilizing hydrocarbon materialwithin the reservoir such that the mobilized hydrocarbon material isconducted through the low permeability zone via the one or more flowpaths; and after the conduction of the mobilized hydrocarbon materialthrough the low permeability zone via the one or more flow paths,producing the mobilized hydrocarbon material.
 5. The process as claimedin any one of claims 1 to 4; wherein: the mobilizing is effected bystimulation with a production-initiating fluid injected into thereservoir via an injection well, wherein the production-initiating fluidincluding steam; and the conduction is effected by gravity drainage to aproduction well; such that the mobilizing and the conducting is effectedby a SAGD process.
 6. The process as claimed in claim 5; wherein the lowpermeability zone is disposed between a horizontal section of theinjection well and a horizontal section of the production well.
 7. Theprocess as claimed in claim 6; wherein at least a continuous portion ofthe permeability zone is disposed between a horizontal section of theinjection well and a horizontal section of the production well, and thecontinuous portion has an axis, and the axis has a length of at least 50metres.
 8. The process as claimed in claim 7; wherein: the injection andproduction wells define a first well pair; and the at least a continuousportion of the low permeability zone is also extending across at least ⅓of a spacing distance between the first well pair and a second wellpair.
 9. The process as claimed in claim 7; wherein: the injection andproduction wells define a first well pair; and the at least a continuousportion of the low permeability zone is disposed between the horizontalsections of the first and second wells and is also extending frombetween the horizontal sections and towards a second well pair by adistance of at least 25 metres.
 9. The process as claimed in claim 6;wherein: the injection and production wells define a first well pair;and at least a continuous laterally-extending portion of the lowpermeability zone is disposed between the horizontal sections of thefirst and second wells and is also extending across at least ⅓ of aspacing distance between the first well pair and a second well pair. 10.The process as claimed in claim 6; wherein: the injection and productionwells define a first well pair; and at least a continuouslaterally-extending portion of the low permeability zone is disposedbetween the horizontal sections of the first and second wells and isalso extending from between the horizontal sections and towards a secondwell pair by a distance of at least 50 metres.
 11. The process asclaimed in claim 5; wherein the low permeability zone is disposed abovea horizontal section of the injection well.
 12. The process as claimedin claim 11; wherein the low permeability zone is disposed above thehorizontal section of the injection well by a minimum distance of lessthan 15 metres.
 13. The process as claimed in claim 11 wherein the lowpermeability zone is disposed above the horizontal section of the welland at a height of less than 35 metres above the bottom of thereservoir.
 14. The process as claimed in any one of claims 1 to 13wherein the low permeability zone has an absolute permeability of lessthan 1000 millidarcies.
 15. The process as claimed in any one of claims1 to 13; wherein the low permeability zone has an absolute permeabilityof less than 10 millidarcies.
 16. The process as claimed in any one ofclaims 1 to 15; wherein the low permeability zone has a dimension of atleast 10 metres.
 17. The process as claimed in any one of claims 1 to15; wherein at least a continuous portion of the low permeability zoneis disposed within a horizontal plane within the reservoir, wherein thehorizontal plane-disposed continuous portion of the low permeabilityzone is characterized by an area of at least 100 square metres.
 18. Aprocess for producing hydrocarbon material from a reservoir, comprising:cooling at least a portion of a low permeability zone within thereservoir such that stress is reduced within the at least a portion of alow permeability zone; pressurizing the cooled portion of the lowpermeability zone with effect that one or more flow paths are formedthrough the low permeability zone; and receiving hydrocarbon material,that is conducted through the one or more of the flow paths, within aproduction well; and producing the received hydrocarbon material. 19.The process as claimed in claim 18; wherein the pressurizing is effectedin response to hydraulic fracturing.